A daughter colony is formed in Volvox by

Options

A. Fission
B. Gonidium
C. Budding
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about how a daughter colony is formed in Volvox, which is a type of green algae.

2. **Identifying the Reproductive Method**: In Volvox, the formation of daughter colonies occurs through a specific reproductive process. The options given are fission, gonidium, budding, and all of the above.

3. **Analyzing Each Option**:
- **Fission**: This is a method of asexual reproduction where an organism divides into two or more parts. However, fission is not the method used by Volvox for forming daughter colonies.
- **Budding**: This is another asexual reproduction method where a new organism develops from an outgrowth or bud on the parent. While budding is common in some organisms, it is not the method used by Volvox.
- **Gonidium**: This is a specialized reproductive cell in Volvox. During asexual reproduction, certain cells in the colony enlarge and differentiate into gonidia.

4. **Describing the Formation of Gonidia**: In Volvox, during asexual reproduction, cells from the posterior part of the colony become reproductive. These cells enlarge significantly (up to 10 times their original size), become rounded, and lose their flagella. These transformed cells are called gonidia.

5. **Conclusion**: Since fission and budding do not occur in Volvox, the correct answer is that a daughter colony is formed by gonidia.

**Final Answer**: A daughter colony is formed in Volvox by gonidium.

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